BAGHDAD, Iraq — Electricity output has dipped to its lowest point in three years in Iraq, where the desert sun is rising toward another broiling summer and U.S. engineers are winding down their rebuilding of the crippled power grid.

The Iraqis, in fact, may have to turn to neighboring Iran to help bail them out of their energy crisis — if not this summer, then in years to come.

The overstressed network is producing less than half the electricity needed to meet Iraq’s exploding demand. American experts are working hard to shore up the system’s weaknesses as 100-degree-plus temperatures approach beginning as early as May, driving up usage of air conditioning, electric fans and refrigeration.

If the summer is unusually hot, however, “all bets are off,” said Lt. Col. Otto Busher, an engineer with the U.S. Army’s 4th Infantry Division.

“We’re living miserably,” said housewife Su’ad Hassan, a mother of four and one of millions in Baghdad who have endured three years of mostly powerless days under U.S. occupation. Her family usually goes without hot water and machine washing, she said, and “often my children have to do their homework in the dim light of oil lamps.”

Project seen as a successDespite such hardships, Army Corps of Engineers officers regard their Restore Iraq Electricity project as one of the great feats in corps history, along with the building of the Panama Canal a century ago.

Their efforts and related programs, at a three-year cost of more than $4 billion and tens of thousands of man-hours, built or rehabilitated electric-generating capacity totaling just over 2,000 megawatts — equaling the output of America’s Hoover Dam.

“It’s not a disappointment, not in my opinion. We’ve added megawatts to the grid,” said Kathye Johnson, reconstruction chief for the joint U.S. military-civilian project office in Baghdad.

For one thing, deprived areas outside the Iraqi capital are doing better, with a nationwide average of 10 to 11 hours of electricity daily, compared with three to five hours in Baghdad. That represents a reshuffling of priorities from prewar days, when the Baathist government diverted flows from northern and southern power plants to this central metropolis.

Although the U.S. effort helped boost Iraq’s potential generating capacity to more than 7,000 megawatts, available capacity has never topped 5,400, held down by plant breakdowns and shutdowns for maintenance, fuel shortages and transmission disruptions caused by insurgent attacks, inefficient production, sabotage by extortionists, and other factors.

In the first week of February, a busy maintenance period, output dropped to 3,750 megawatts, reports the joint U.S. agency, the Gulf Region Division-Project Contracting Office. That’s a new low since the period immediately after the 2003 U.S. invasion.

Transitioning to Iraqi responsibilityNow the U.S. reconstruction money is running out, the last generating project is undergoing startup testing in southern Iraq, and the Americans view 2006 as a year of transition to full Iraqi responsibility, aided by a U.S. budget for “sustainability,” including training and advisory services.

Even that long-term support may fall short, however. The reconstruction agency allotted $460 million for this purpose, but in a report to Congress on Jan. 30 the special inspector-general for Iraq reconstruction estimated $720 million would be needed.

The decline of Iraq’s electrical system can be traced back at least to the 1991 Gulf War, when U.S. warplanes targeted the grid. The government rebuilt the system to produce 4,400 megawatts, still short of demand. But damage from the 2003 invasion — and particularly from looting that followed — knocked production down to 3,200 megawatts and wrecked transmission lines.

The Army engineers who rolled into Iraq in 2003 found power plants barely operating, lacking spare parts and suffering from years of neglect brought on by U.N. trade sanctions. They brought in contractors to upgrade installations, but the looting and sabotage went on. Insurgents attacked fuel pipelines. Other Iraqis toppled transmission towers to keep power in their own cities and away from Baghdad.

To battle the insurgency, U.S. authorities shifted more than $1 billion from power projects to security spending. Having planned to add or rehabilitate 3,400 megawatts’ worth of power production, they settled instead for 2,000. The lack of security also slowed work: Fewer than half the 350 local power-distribution projects planned by the Americans had begun as of early this year, the inspector-general reported Jan. 30.

“It’s problems, rather than mistakes,” said Mohamoud al-Saadi, an Iraqi Electricity Ministry official, citing the sabotage and insurgency.

A crucial mistake?But some believe the Americans also made a critical mistake by installing gas-turbine generators rather than building or overhauling more of the oil-fueled, steam-run plants.

Iraq doesn’t have pipelines to deliver natural gas from its oil fields, so plant operators resort to low-grade oil to run the gas-combustion engines, reducing power output by up to 50 percent and potentially damaging the machinery.

He said the system risked losing 300 megawatts more in hydroelectric power because the Tigris River was running extremely low. But a recent agreement by Turkey to release more upriver water appears to have lifted that threat.

Energy from Iran could be an optionOne solution could be power from Iran: one Iraqi proposal is for a transmission line to import much more than the 100 megawatts of Iranian power Iraq now buys.

The U.S. Embassy won’t talk about it, in view of Washington’s animosity toward Tehran over its nuclear ambitions. But the reconstruction office’s Waters said one of the U.S.-financed Iraqi substations under construction could handle more Iranian power.

“Completing an Iran transmission line could give them up to 1,500 megawatts,” said Army engineer Moff.

Even if a major Iran linkup is built, however, other projects may stay in the blueprint stage unless more aid is forthcoming from Washington or other donors.

“We have a lot of unfinished projects because of a lack of government funding,” said the Electricity Ministry’s al-Saadi.

A $20 billion undertakingReconstruction chief Johnson agrees with Iraq’s five-year cost estimate. “It’s probably in the range of $16 to $20 billion to complete the infrastructure to provide 24/7 sustainable power to all the citizens of Iraq,” she said.

In the long term, Johnson said, it’s essential for Iraq to open its power industry to private investment. That would mean making it profitable by following the advice of the World Bank and others to raise rates; Iraqis now pay 50 cents to a dollar a month.

Can people afford more?

Hassan’s family already cannot afford fuel for its small generator. “Most of the time we can’t use it,” the Baghdad housewife said.

Whether she and others can afford higher rates, a classic “chicken and egg” problem confronts energy-short Iraq, said Moff.

“Before you can raise rates,” he pointed out, “you have to have power.”